EVS ppt.pptx

8/14/2019 EVS ppt.pptx

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According to WHO(World Health Organization)Air Pollution is contamination of the indoor or outdoorenvironment by any chemical, physical or biologicalagent that modifies the natural characteristics of the

atmosphere.


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There are two types of pollutant

(A pollutantis a substance or energy introduced into theenvironment that has undesired effects, or adversely

affects the usefulness of a resource)

Primary pollutants

Secondary pollutants


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Primary pollutants are those that are emitted directly

into the air from pollution sources. Examples

Garbage burning gas emission from industries


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Secondary pollutants are formed when primary pollutants

undergo chemical changes in the atmosphere. e.g.:- ozone


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ANTHROPOGENIC SOURCES

IT INCLUDES:

1.STATIONARY SOURCE:

IT REFERS TO AN EMISSION

SOURCE THAT DOES NOT

MOVE,ALSO KNOWN AS A POINT

SOURCE. eg:factories,power plants and

dry cleaners.

2.AREA SOURCES:

IT IS USED TO DESCRIBE MANY

SMALL SOURCES OF AIR POLLUTION

LOCATED TOGETHER WHOSEINDIVIDUALS EMISSIONS MAY BE

BELOW THRESHOLDS OF

CONCERN,BUT WHOSE COLLECTIVE

EMISSIONS CAN BE SIGNIFICANT.

Eg:residential wood burners


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MOBILE SOURCESA mobile source of air pollutionrefers to a source that is capableof moving under its own power.

In general, mobile sourcesimply on-road transportation,which includes vehicles such ascars, sport utility vehicles, andbuses.

In addition, there is also anon-road or off-road categorythat includes gas-powered lawntools and mowers, farm and

construction equipment,recreational vehicles, boats,planes, and trains.


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Agricultural

Sources

Agricultural operations those that raise

animals and grow crops, can generate

emissions of gases and particulate

matter.

For example, animals confined to barn

or restricted area (rather than field

grazing ), produce large amounts of

manure. Manure emits various gases,

particularly ammonia into the air.

This ammonia can be emitted from the

animal houses, manure storage areas, or

from the land after the manure is

applied. In crop production, the

misapplication of fertilizers, herbicides,

and pesticides can potentially result in

aerial drift of these materials and harm

may be caused.


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Natural sourcesAlthough industrialization and

the use of motor vehicles are

overwhelmingly the most

significant contributors to air

pollution, there are important

natural Sources of pollutionas

well Wild land fires, dust storms,

and volcanic activity also

contribute gases and particulates

to our atmosphere.

Unlike the above mentioned

sources of air pollution, natural

air pollution is not caused by

people or their activities.


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FEW OTHER SOURCES OF AIR POLLUTION:

1.INDUSTRIES:Gases emitted from chimneys cause

air pollution

2.FESTIVALS LIKE DIWALI


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It is estimated that the annual. carbon dioxide

emissions from fireworks is 60,340 tensor the same

emissions from 12,000 cars on the road for a year!!

If one suggests that planting trees is a solution,

then, please be informed that itd take the entire

lifetime of 5,000 trees to offset the 60,000 tons of

carbon emissions produced in this one day!!

Not only it pollutes the environment, it also

causes many deadly air-borne diseases.

Hence it is important to avoid use of fireworks

during our festivals


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Air pollution results in air quality degradation

Affects the quality of other environmentalresources as well as human-made structures

Impairs visibility and contributes to climatechange

Can also be detrimental to human health


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Polluted Air is Harmful to Park

resources such as

Vegetative discoloration

Growth disruption from ozoneLoss of aquatic species from streamacidificationErosion of building surfaces and rockformationsShifts in nutrient availability from aciddeposition


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Major Effects of Air Pollution

Acid Rain

Rainfall madesufficiently acidic byatmospheric pollutionthat it causesenvironmental harm,typically to forests andlakes.

Global WarmingA gradual increase in the overall temperatureof the earth's atmosphere generally attributed

to the greenhouse effect.


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Excessive richness of nutrients in a lake or

other body of water causing a dense growthof plant life and death of animal life fromlack of oxygen.

Health EffectsSuch as irritation to the eyes, nose andthroat, and upper respiratory infections.

The Thinning Ozone LayerAir pollutants called CFCs have destroyed

parts of the ozone layer thus thinning theozone la er.


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Photochemical smog is a term used to describe air pollution that is a result of

the interaction of sunlight with certain chemicals in the atmosphere. Mixture of air pollutants

Nitrogen oxides (NOX)

Ozone

Volatile organic compounds (VOCs)

Peroxyacyl Nitrates (PAN)

One of the primary components of photochemical smog is ozone.

While ozone in the stratosphere protects earth from harmful UV radiation,

ozone on the ground is hazardous to human health.

Ground-level ozone is formed when vehicle emissions containing nitrogen

oxides (primarily from vehicle exhaust) and volatile organic compounds(frompaints, solvents, and fuel evaporation) interact in the presence of sunlight.

Therefore, some of the sunniest cities are also some of the most polluted.


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To the right is Los Angeles on asmog-filled day and a smog free day.

The haze is due to the presence of

aerosols and particulates.

The second picture is of Gateway

Arch in St. Louis. The left is clear

day in April, the right is a hazysmoggy August day.

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1. Human Health

Smog is a serious problem in many cities and continues to harm human health.

According to the American Lung Association, your lungs and heart can be

permanently affected by air pollution and smog.

Anyone with both short and long term exposure can suffer ill health effects.

Ground-level ozone, sulfur dioxide, nitrogen dioxide and carbon monoxide areespecially harmful for senior citizens, children, and people with heart and lung

conditions such as bronchitis, and asthma.

It can inflame breathing passages, decrease the lungs' working capacity, cause

shortness of breath, pain when inhaling deeply, wheezing, coughing, fatigue,

increased asthma-related symptoms and even lung cancer. It can cause eye andnose irritation.

Increased hospital admissions and premature death.


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2. Damage to materials

O3causes cracking and aging of rubber by oxidizing and breaking double bondsin polymer.

3. Effect on the Atmosphere

Reduced visibility.

4. Toxicity to Plants Reduction to growth and yield.

Damage to vegetation.

Damage to crops.


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Two factors influencing the formation of photochemical smog

1. Topography

Very important for

formation of photochemicalsmog.

Restriction of air movement,

city in valley experience more

smog problem, than plains.


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2. Temperature Inversion

Increase of air temperaturewith height for some distance

above ground causing the smog

trapped close to ground.

Consequences

Air becomes still and dustand pollutants are no longer

lifted from surface.

Serious problem in many cities.


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